I can't recall the guys name, but the sculptor died. That is why it was never finished.

"The original design had the Presidents head to waist, but due to high costs, only the heads were completed." "Due to unforeseen vulnerabilities in the granite, Lincoln and Jefferson were moved from the locations in Borglum's original design. Lincoln was relocated to the spot that Borglum had planned to include an 80 by 100 foot inscription in the shape of the Louisiana Purchase. To replace the inscription, Borglum conceived another grand addition to the monument of similar proportions: the Hall of Records. The Hall of Records was to include a grand entrance to an 80 by 100 foot vault carved directly into the granite face of the small canyon behind Lincoln’s head. Borglum envisioned 800 granite steps leading from his studio to the entrance of the Hall. In 1938 Borglum and his crew began to carve this grand hall, where he envisioned the original Declaration of Independence and United States Constitution should eventually be stored. But a combination of unexpectedly hard granite, looming war in Europe, and lack of funding conspired against Borglum’s last dream, though his plans became more elaborate as his team rushed to complete this work. They reached 70 feet into the granite by the time Borglum unexpectedly died in March 1941. The monument was deemed complete and all work shut down on October 31 of the same year. Though Borglum’s children tried over the years to renew interest in their father’s last dream, it was not until 1998 that the National Park System, together with the Borglum Family, put “finishing touches” on the Hall of Records. A titanium vault was installed in the granite floor of the unfinished hall, and filled with sixteen porcelain enamel panels that include the United States Constitution and other important historical documents. The Hall of Records entrance can be seen from west-facing aerial photographs of the monument from Live Search Maps." Source and further information: http://en.wikipedia.org/wiki/Construction_of_Mount_Rushmore Further information: http://www.engineeringsights.org/SightDetail.asp?Sightid=526&id=SD&view=s&name=South+Dakota&page=1&image=0